H1N1

Influenza A H1N1 2009, aka Swine Flu, is a new strain of influenza virus not previously seen. This strain is unusual in that it appears to be a cross between swine Influenza A H1N1 viruses found in North America, Asia, and Europe, as well as North American avian influenza viruses, and human influenza viruses.[1] To avoid misunderstandings, as of April 30, 2009, the World Health Organization is now referring to the virus as 2009 Influenza A H1N1. Although the virus does contain elements of swine Influenza, there is no documented risk from eating pork. To date, only those in close contact with swine (farmers/handlers) have ever contracted a Swine influenza infection from pigs themselves. [2]

The virus was first identified in the US in two children on April 17. [3] It appears to have first occurred in La Gloria, Mexico in March, when there was a large outbreak of an unusual respiratory illness in the town. [4] Since then, it has now spread to and been identified in multiple countries, including the US, Canada, New Zealand, Hong Kong, China, and throughout Europe.

For perspective, as Dr Margaret Chan Director-General of the World Health Organization, observed, balancing information alerts can be a difficult challenge: "Last week, Mexican researchers published clinical profiles of early H1N1 cases in the New England Journal of Medicine. As noted, the full clinical spectrum of this disease is not yet fully understood. We do not fully understand the predictive factors for severe or fatal infections. However, as more and more data become available, we are getting a better grip on warning signs that can signal the need for urgent medical care. Symptoms of concern include difficulty in breathing, shortness of breath, chest pain and severe or persistent vomiting. In adults, a high fever that lasts for more than three days is a warning sign, particularly when accompanied by a general worsening of the patient’s condition. Lethargy in a child, that is, a child that has difficulty waking up or is no longer alert, or is not playing, is a warning sign. For a pandemic of moderate severity, this is one of our greatest challenges: helping people to understand when they do not need to worry, and when they do need to seek urgent care. This is one key way to help save lives."[5]

Summary of Key Points for Protection

These are the essential points to understand to protect yourself and your community: see How Influenza A H1N1 is Spread see Household Infection Control Precautions

The mode of transmission of influenza viruses is thought to occur from person to person in respiratory droplets of coughs and sneezes. These infected droplets land on the mouth, nose or eyes of people nearby, or are spread when a person touches respiratory droplets on another person or an object and then touches their own (or another person's) mouth or nose (or rubs their eyes) before washing their hands. Influenza A H1N1 is not spread by pork or other food.

Masks will provide barrier protection against the large infective droplets that are believed to cause transmission. They are not effective against small viral particles that may be airborne. N-95 masks must fit tightly to work effectively. [6] Don’t panic if you do not have an N-95 surgical mask. An important part of prevention is to keep droplets away from your nose, mouth, and eyes. If you don't have a surgical mask, use a cloth bandana or similar to cover your nose and mouth. While there may be airborne transmission, droplets are probably a significant route and the one that individuals can best protect against through good hygiene practices.

The essence of protecting yourself: Practice good hygiene. Keep your hands away from your face, or wash them first.

Wash your hands often.Wash with soap and water. Utilize hot water and scrub with soap for 30 seconds, including between fingers and under fingernails. Be sure to use a (paper) towel to turn off the faucet handles so as not to recontaminate your hands. The same applies to doorknobs. If you can't wash your hands, use an alcohol-based hand sanitizer with at least 60% alcohol.

Cover coughs and sneezesTeach your family to cover their nose and mouth when they cough or sneeze, dispose of the used tissues promptly, and wash their hands (or use alcohol-based hand sanitizer) immediately, before they contaminate other surfaces with infective secretions.

"Social distancing" Keep ill family members away from others in the home and at home unless they need medical care. If ill and you have to go out, wear a mask to catch coughs and sneezes and reduce the transmission of infective droplets to others. In general, do not share drinks or eating utensils. Do not share towels. Color coding towels for different family members can help reduce spread, too.

Seek medical care promptly if you have a serious underlying disease (see Risk Factors), are pregnant, or become ill with severe flu-like symptoms or warning signs of more serious illness – such as:

shortness of breath or difficulty breathing, especially if the patient is turning blue

bloody or purulent sputum

chest pain (other than with coughing)

altered mental status

high fever that persists beyond 3 days

low blood pressure.

Milder symptoms of influenza, including fever, generalized aches, sore throat, cough, runny nose, vomiting, and diarrhea, can be treated at home, symptomatically, since antiviral medication is no longer recommended except for high risk individuals or those developing complications. Take precautions if visiting your healthcare provider, including washing your hands frequently, using mask or cover over mouth and nose, and distancing yourself from others as much as possible to prevent further spread. See Treatment.

Warning Do not give aspirin (acetylsalicylic acid) to children or teenagers who have the flu; this can cause serious and possibly fatal Reyes syndrome.[7] NSAIDS such as ibuprofen and acetaminophen (Tylenol) are safe for symptomatic relief.